Fluid-pressure railway-brake.



No. 881;751. PATEN'IED MAR. 10, 1903.

' W. A WEANT. v

I FLUID PRESSURE RAILWAY BRAKE.

APPLIGATION nLnnssrmso. 1907.

, 2 SHEETS-SHEET 1.

No.881,751. PATENTED MAR.10, 1908. W. A. WEANT.

FLUID PRESSURE RAILWAY BRAKE.

APPLICATION-FILED $EPT.30.1907.

ZSHEETS-SHEET 2.

WILLIAM A. WEANT, OF MOCKSVILLE, NORTH CAROLINA.

' FLUID-PRESSURE RAILWAY-BRAKE.

Specification of Letters Patent.

Patented March 10, 1908 Application filed September 30, 1907. Serial No.395,185.

To all whom it may concern:

Be it known that I, WILLIAM A. WEANT, a citizen of the United States,residing at Mocksville, in the county'of Davie and State of NorthCarolina, have invented new and useful Improvements in Fluid-PressureRailway-Brakes, of which the following is a specification.

This invention relates to fluid pressurerailway brakes, and one of theobjects thereof is to provide means in a manner as hereinafter set forthfor automatically closing a pressure retaining valve to overcome leakagewhen the maximum brake pressure has been applied and the brakes heldl Afurther object of the invention is to provide means in a manner ashereinafter set forth whereby the brakes can be locked and retained insuch position after the air. has

been exhausted from the brake cylinder.

A furtherobject of the invention is to provide means in the manner ashereinafter set forth for automatically releasing the brakes from lockedposition.

A further object of the invention is to provide means in the manner ashereinafter set forth whereby the brakes can be manually locked.

A further object of the invention is to provide attachments for airbrakes for automatic ally closing a pressure retaining valve and forholdingthe brakes locked when applied after the pressure has beenexhausted from the brake cylinder, and which shall be simple inconstruction, strong, durable, efficient in its use, readily set up, andcomparatively inexpensive to manufacture.

With the foregoing and other objects in view, the invention consists ofthe novel construction, combination and arrangement of parts hereinaftermore specifically described "and illustrated in the accompanyingdrawings wherein is shown the preferred embodiment of the invention, butit is understood that changes, variations and modifications can beresorted to which come within the scope of the claims hereunto appended.

In describing the invention in detail, reference is had to theaccompanying drawings wherein like reference characters denotecorresponding parts throughout the several views, and in which Figure 1is a side elevation of a car, broken away, showing the adaptation of theattachments for fluid pressure railway brakes in accordance with thisinvention,v Fig. 2 is an inverted plan of the car showing thearrangement of the air brake attachments in accordance with thisinvention. Fig. 3 is a side elevation of the brake cylinder, showing theadaptation therewith of the attachments in parts being shown insections. Fig. 4 is a plan of the elements shown in Fig. 3. Fig. 4 is adetail showing the position of the pressure retaining valve when theparts are arranged accordance with this invention, certain of the in themanner as shown in Figs. 3 and 4..

Fig. 5 is a sectional detail, and Fig. 5 is a view similar to Fig. 4*,showing the position of the valve when the parts are set in the positionshown in Fig. 5.

Referring to the drawings by reference characters, 1 denotes a brakecylinder and 2 the piston rod projecting therefrom, which are of knownconstruction. Mounted upon the rod 2 is a sleeve 3 provided at one endwith a pair of ears 4 to which are pivotally connected a brake beam 5.The sleeve 3 is formed with an inwardly extending annular shoulder 6,against which abuts one end of a coil spring 7 surrounding the pistonrod 2. The other end of the said spring 7 is connected to a collar 8afiixed to the piston rod 2. The latter carries forwardly of the brakebeam 5 a short sleeve 9, provided with an extension 10 having theforward end thereof beveled as at 11 and formed with shoulders 12 and13, against which is adapted to'engage a locking dog 14 for maintainingthe piston rod 2 in an out position when the brakes are applied andafter the pressure has been exhausted from the brake cylinder.

From the foregoing construction and arrangement of arts it is evidentthat the engineer can ho d the brakes applied while at the same timereducing the pressure in the brake cylinder, and in such connection itwill be stated that it will be assumed, by way of example, that themaximum pressure is 60 lbs-and that the brakes can be applied at 40 lbs;when such amount of pressure is had upon the piston within the brakecylinder 1, the piston rod 2 is forced outwardly and the brakes applied.To maintain the brakes in this instance, it is necessary to hold thepressure, but to overcome this holding of the pressure, at the same timemaintaining the brakes in the afpplied position, an additional pressure,say 0 ten pounds, is applied to the piston and which causes the istonrod to move outwardly so that the co lar 9 will ride under the dog 14and the latter will have its free end engage against one of theshoulders of the collar 9. The pressure being released, the rod 2 willtend to move inwardly owing to the action of the spring 7 and the springwithin the brake cylinder, but this inward movement of the rod 2 will bearrested by the dog 14 and collar 9, consequently the piston rod 2 willbe maintained in its out position and the brakes will be held'applied.When the piston rod 2 is moved outwardly after the initial applicationof pressure, the sleeve 3 moves therewith and actuates the beam 5, aswill be evident, but upon the second application of pressure, the sleeve3 remains stationary while the piston rod 2 moves outwardly andcompresses the spring 7. Normally, unless it is desired to maintain thebrakes in the locked position for a predetermined time, the secondapplication of pressure is not made. The second application of pressureis made when it is desired to lock the entire train and at the same timereduce the pressure in the brake cylinder. If the train should be lookedthrough the medium of the dog 14 and the collar 9, and it be desired torelease the brakes, a third a )plication of pressure, say of 10 lbs, ishac upon the piston in the brake cylinder 1 so as to shift the collar 9entirely clear of the dog 14, the latter assuming the position as shownin Fig. 5. Now, if the pressure is reduced, the action of the spring 7and the spring within the brake cylinder will cause the rod 2 to moveinwardly, the action being such that the collar 9 will quickly pass thedog 14 when the brakes are released. Preferably the lock for the brakesis used to lock a train on a siding for an indefinite time withoutholding the pressure within the brake cylinder, or in other words itallows for the exhaust of the fluid pressure after the necessaryapplications have been made to set the lock, the latter maintaining thebrakes applied.

In Fig. 2 means is shown connected to the piston rod 2 whereby the lockcan be applied manually, irrespective of the application of fluidpressure, and in this connection it will be stated that to the end ofthe piston rod 2 is attached a chain or cable 15, which winds upon adrum 16, carried by a spindle 17 suspended in the hangers 18 dependingfrom the bottom of the car 19, or the cable may be attached to avertical hand brake staff similar to that now used and so as to providean emergency stop. A crank handle 20 is provided upon each end of thespindle 17 to allow of the revolving of the spindle 17 for the pur oseof applying and releasing the lock. f the vertical staff is used, theordinary hand wheel is employed for revolving the stafi. The lock is setby winding the chain or cable 15 upon the drum 16 which draws the rod 2out until the dog 14 which is suspended from the bottom of the car, bythe keepers 21, engages one of the shoulders of the collar 9 which willprevent the rod 2 from moving inwardly. The drawing out of the rod 2 inthe manner as stated will cause the application of the brakes and a.further movement of the rod 2 will cause the dog 14' to engage one ofthe shoulders of the collar 9 and lock the rod from moving imvardly,thereby maintaining the brakes applied. If it be desired to release thebrakes, the chain or cable 15 is wound further upon the drum 16 whichdraws the collar clear of the dog 14. The spindle is then released, therod 2 is moved inwardly and the collar 9 passes the dog 14. hen the rod2 is pulled outwardly through the action of winding the chain or cable15 upon the drum it, the spring 7 and the spring within the brakecylinder will be compressed, as is evident, and when the collar 9 isclear of the dog 14 and the spindle 17 is released, the action ol thesprings will draw the rod 2 inwardly.

The attachment further comprises a means 0 erated from the piston rod 2for automatically closing a pressure retaining valve when the maximumbrake pressure is applied, so as to prevent leakage during the holdingof the brakes. The pressure retaining valve is so mounted andconstructed that it will not be brought to a full close unless themaximum brake pressure is applied; by way of example, it will be statedthat it the maximum brake pressure is fifty pounds, and but thirty-fiveor forty pounds is applied to the piston in the brake cylinder, althoughthe pressure retaining valve will be actuated, the movement, however,will not be to such extent as to completely close. The said pressureretaining valve is mounted in a. casing 25 which is interposed in anexhaust pi e 23 and positioned exteriorly ol' the triple va ve mechanism24. The pipe 23 communi cates with the exhaust of the triple valvecasing.

The pressure retaining valve which is indicated by the referencecharacter 25" has a. stem 26 projecting from the casing 25 and connectedby an arm 27 to a link 1.8. One end of the link 28 is enlarged andslotted as at 29, and in the slot 29 plays a pin 30 carried by the upperend. of the arm 37 and by such an arrangement a pin and slot connectionis had between the arm 27 and the link 28.. The length of the slot29'1nay be as desired in accordance with the duration of the lostmotion. The other end of the link 28 is pivotally connected as at 31 toa rod 32 coupled by the collar 33 to the piston rod 2,

the collar 33 being fixed to the said piston rod 2. By such anarrangement it is evident that when the brakes are applied the link 25will be carried therewith thereby shifting the arm 27 and actuating theretaining valve within the casing 25. If the maximum brake pressure isapplied, the retaining valve 25 will be completely closed; if thepressure applied is below the maximum, the valve 25 will only be partlyclosed. Owing to the pin and slot connection between the arm 27 and thelink 28, the said arm is not immediately shifted when the link 28 iscarried forward by the piston, as the slot 29 provides for lostmoslightly rearwardly such action carrying the link therewith, themovement of the link be ing sufficient to slightly shift the arm 27 andthe slight movement of the arm 27 partlyopens the valve 25 This allowsof an exhaust from the brake cylinder through the triple valve mechanismand valve 25*. The exhaust from the brake cylinder allows of the pistonto further move inwardly which action carries the link therewith andimparts a further shifting movement to the arm 27, consequentlyincreasing the exhaust opening as the valve 25 is further shifted toopen position. This action is continued until the valve 25 is completelyopened so that the brake cylinder will be entirely exhausted, that is tosay if the manually operated retaining valve is set so that a freeexhaust is had to the atmosphere. Of course, if the manually operatedretaining valve is set so that the exhaust will be had against theaction of the weight which forms a part of the manually operatedpressure retaining valve, it is evident that a certain amount ofpressure will be held in the brake cylinder to furnish a sufficientretarding power to prevent a too rapid acceleration of the train speed.After the extreme application is made the piston rod will move back adistance due partly to the looseness of the brake rigging and to theleaking of air past the brake piston, so that when the movement of thetriple valve occurs for brake release the lost motion, owing to the pinand slot connection, will have been taken up. In this case, however,dependence upon the looseness of the valve 25 would have to be reliedupon for initial movement of the arm 27. Preferably reliance for initialmovement is had for release by setting up the valve 25 in such a manner,

(grooved by way of example) that the air will not be completely orentirely out off by the valve, but the valve will allow suflicientescape of air so as to let the piston rod come gradually back. This willgive suflicient time to change the auxiliary reservoir before the brakesare entirely released. The manually operated retaining valve is of knownconstruction, so consequently it is unnecessary to describe it. The pinand slot connection between the arm 27 and the link 28 provides meanswhereby the pressure retaining valve 25 is not shifted to open positionuntil after the exhaust of the triple valve is opened, that is to say,although the triple valve exhaust may be open, yet the brake pressure isretained in the brake cylinder until the pressure retaining valve 25starts to open. The pin and slot connection between the arm 27 and thelink 28 furthermore provides means to prevent a too sudden actuation ofthe pressure retaining valve in either direction.

hat I claim is 1. A fluid pressure railway brake provided with meansoperated by the piston rod of the brake cylinder for actuating apressure retaining valve when the brakes are applied and released.

2. A fluid pressure railway brake comprising the combination with atriple valve mechanism and its exhaust, of a brake cylinder having apiston rod projecting therefrom, a pressure retaining valve interposedin the exhaust of the triple valve mechanism, an arm connected to thestem of said retaining valve, and connections between said arm and saidrod for actuating said arm to shift the valve during the application andrelease of the brakes.

3. A fluid pressure railway brake comprising a pressure retaining valve,an arm connected to the stem of said valve, a brake cylinder embodying apiston, and piston rod, a link connected with the piston rod and shiftedduring the application and release of the brakes, and a pin and slotconnection between said arm and said link, said link causing theactuation of said arm and shifting of said pressure retaining valve whenactuated by the piston rod.

4. A fluid pressure railway brake comprising a brake cylinder embodyinga piston and an elongated piston rod, a sleeve mounted upon said pistonrod, a brake beam pivotally connected to said sleeve,-a collar mount--ed upon the rod, a coil spring arranged within said sleeve, having oneend abutting against the'sleeve and its other end affixed to saidcollar, a dog suspended from the bottom of the car, and a shoulderedcollar carried by the rod and adapted to be engaged by the dog when thepiston rod is moved outwardly, thereby arresting the inward movement ofthe rod and maintaining the brakes applied.

5. A fluid pressure railway brake comprising a brake cylinder embodyinga piston and an elongated piston rod, a sleeve mounted upon said pistonrod, a brake beam pivotally connected to said sleeve, a collar mountedupon the rod, a coil spring arranged within said sleeve, having one endabutting against the sleeve and its other end aflixed to said collar, adog suspended from the bottom of the car, a shouldered collar carried bythe rod and adapted to be engaged by the dog when the piston rod ismoved outwardly, thereby arresting the inward movement of the rod andmaintaining the brakes applied, and means whereby the dog and shoulderedcollar are moved out of engagement to allow of the return of the pistonrod.

6. A fluid pressure railway brake embodyl l 1 l l l I l l l ing anautomatically operable pressure retaining valve exteriorly of the triplevalve mechanism and means connected with said valve and with the pistonrod of the brake cylinder for actuating said valve when the brakes areapplied and released.

In testimony whereof I have hereunto set my hand in presence of twosubscribing witnesses.

WILLIAM A. WEANl. Witnesses JOHN L. FLETCHER, N. LoUIs BOGAN.

